The University of Utah Cancer Center Flow Cytometry Facility is severely limited by an antiquated optical bench, which is urgently in need of replacement. Current problems include an inability to expand to 4-5 color fluorescence detection, inadequately powered laser for current needs, inefficient sorting, and non-availability of parts and service contract on our current outdated instrument We are applying through the Shared equipment grant mechanism to replace the main flow cytometer in the University of Utah Cancer Center sponsored Flow Cytometry Facility with a state of the art instrument The University of Utah will provide technician support and pay for maintenance of service contracts on the optical bench, computer and lasers. The University is also recruiting a nationally recognized Flow Cytometry facility director to oversee the function of this core facility. A large number of currently funded investigators working in several different departments at the University have applications for this instrument in their work. A diverse spectrum of research topics are represented among users, including cell biology (apoptosis, cell adhesion, proteolysis, extracellular matrix, signal transduction, peptide regulatory factors, cell polarization), immunology (lymphocyte and macrophage cytotoxicity, cytokine biology, demyelinating diseases, arthritis, thermal injury, antigen presentation, bone marrow transplantation ), microbiology, and molecular genetics (regulation of DNA replication, antibody repertoire and diversity, embryogenesis, somatic mutation, genetic therapy). Improvement of the Cancer Center Flow Cytometry facility would greatly enhance the ability of these investigators in performing their peer-reviewed and well funded research.